Comments on: How to Become a Human Calendar http://litemind.com/how-to-become-a-human-calendar/ Exploring ways to use our minds efficiently. Fri, 06 Nov 2009 19:19:17 -0600 http://wordpress.org/?v=2.8.5 hourly 1 By: Luciano Passuello http://litemind.com/how-to-become-a-human-calendar/#comment-40084 Luciano Passuello Sat, 10 Oct 2009 14:31:50 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-40084 Hi Jason, The part you got it wrong is that 99 mod 7 is not 14, but 1. <em>MOD</em> is the remainder of the division, not the quotient (that would be <em>DIV</em>)... I used to get it wrong all the time, too! :) Hi Jason,

The part you got it wrong is that 99 mod 7 is not 14, but 1. MOD is the remainder of the division, not the quotient (that would be DIV)… I used to get it wrong all the time, too! :)

]]> By: Jason http://litemind.com/how-to-become-a-human-calendar/#comment-40081 Jason Sat, 10 Oct 2009 14:05:48 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-40081 I saw this and got really excited, but I can't figure out where I'm going wrong with July 4, 1776. (4+76+(76/4)) = 99 mod 7 is 14 so year code is 2. (2+0+4) = 6 So it should be a friday, but it's a thursday. I don't see where I'm going wrong. I saw this and got really excited, but I can’t figure out where I’m going wrong with July 4, 1776. (4+76+(76/4)) = 99 mod 7 is 14 so year code is 2. (2+0+4) = 6 So it should be a friday, but it’s a thursday. I don’t see where I’m going wrong.

]]> By: Mati http://litemind.com/how-to-become-a-human-calendar/#comment-39970 Mati Fri, 09 Oct 2009 00:50:43 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-39970 This technique is awesome... I only learned it for fun but then I discovered is far more useful... I use it for example to know the thursdays of a particular month... Just having the first day of the month and adding 7.. Really, It's useful. Thanks for sharing it, man =) This technique is awesome…
I only learned it for fun but then I discovered is far more useful…
I use it for example to know the thursdays of a particular month…
Just having the first day of the month and adding 7..
Really, It’s useful. Thanks for sharing it, man =)

]]> By: Twitter Trackbacks for How to Become a Human Calendar [litemind.com] on Topsy.com http://litemind.com/how-to-become-a-human-calendar/#comment-37791 Twitter Trackbacks for How to Become a Human Calendar [litemind.com] on Topsy.com Tue, 01 Sep 2009 16:13:58 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37791 [...] How to Become a Human Calendar litemind.com/how-to-become-a-human-calendar – view page – cached Exploring ways to use our minds efficiently., Mentally finding out the day of the week for any date is a skill you can easily learn. You don't need to be an autistic genius – all it takes is basic memorization effort and some trivial math. — From the page [...] [...] How to Become a Human Calendar litemind.com/how-to-become-a-human-calendar – view page – cached Exploring ways to use our minds efficiently., Mentally finding out the day of the week for any date is a skill you can easily learn. You don't need to be an autistic genius – all it takes is basic memorization effort and some trivial math. — From the page [...]

]]> By: Luciano Passuello http://litemind.com/how-to-become-a-human-calendar/#comment-37763 Luciano Passuello Mon, 31 Aug 2009 23:57:23 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37763 I had no idea how the system I described here could be derived. Thanks for that --- it's a brilliant piece of reasoning you got there, Jason. <strong>I'm delighted to see how you created a "meta system" for calculating dates!</strong> Your method of 'rolling back' digits is also very ingenious. It seems that it's great to calculate dates that span multiple years (it makes it easy to calculate dates two, three or many years ahead or behind). The method I describe here --- at least the way I use it --- is great for calculating dates in a <em>particular year</em> --- for example, the year we're on. The month codes, although arbitrary, are <em>always</em> the same and, as such, become so second-nature that, in fact, there's only one number left to memorize each year. I'm saving your method for my own reference and future experiments. <strong>Thank you so much for the fresh new look to the calendar method! </strong> I had no idea how the system I described here could be derived. Thanks for that — it’s a brilliant piece of reasoning you got there, Jason. I’m delighted to see how you created a “meta system” for calculating dates!

Your method of ‘rolling back’ digits is also very ingenious. It seems that it’s great to calculate dates that span multiple years (it makes it easy to calculate dates two, three or many years ahead or behind).

The method I describe here — at least the way I use it — is great for calculating dates in a particular year — for example, the year we’re on. The month codes, although arbitrary, are always the same and, as such, become so second-nature that, in fact, there’s only one number left to memorize each year.

I’m saving your method for my own reference and future experiments.
Thank you so much for the fresh new look to the calendar method!

]]> By: Jason http://litemind.com/how-to-become-a-human-calendar/#comment-37685 Jason Sun, 30 Aug 2009 18:03:18 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37685 Hi, Luciano just found your blog the other day. Some really great stuff on here. I started writing a comment a little while ago explaining another method of being able to figure out dates. By the time I got to the end of it I realized that formula you gave could be derived from the method that I used. The whole thing got kind of long so I wrote it up over here if you're interested: http://jason-somuchtodo.blogspot.com/2009/08/mathematical-diversion-calculating.html It also explains why you and Melissa can use different month codes and how you can adjust the whole thing to get monday=1 (actually that's not how I did it but you can) plus making it easier so you don't have to memorize year codes but just calculate them easily on the spot. I wrote the whole thing off the top of my head so it's not terribly well organized but you should be able to follow it. Of course if you already know where the whole thing is derived from then you won't find anything knew in what I've written. But anyway... Hi, Luciano just found your blog the other day. Some really great stuff on here.

I started writing a comment a little while ago explaining another method of being able to figure out dates. By the time I got to the end of it I realized that formula you gave could be derived from the method that I used.

The whole thing got kind of long so I wrote it up over here if you’re interested:
http://jason-somuchtodo.blogsp.....ating.html

It also explains why you and Melissa can use different month codes and how you can adjust the whole thing to get monday=1 (actually that’s not how I did it but you can) plus making it easier so you don’t have to memorize year codes but just calculate them easily on the spot.

I wrote the whole thing off the top of my head so it’s not terribly well organized but you should be able to follow it.

Of course if you already know where the whole thing is derived from then you won’t find anything knew in what I’ve written. But anyway…

]]> By: How To: 121 Ways to Increase Brain Power | Cogent Nirvana http://litemind.com/how-to-become-a-human-calendar/#comment-37400 How To: 121 Ways to Increase Brain Power | Cogent Nirvana Wed, 26 Aug 2009 18:09:14 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37400 [...] Dump the calendar! [...] [...] Dump the calendar! [...]

]]> By: Luciano Passuello http://litemind.com/how-to-become-a-human-calendar/#comment-37037 Luciano Passuello Thu, 20 Aug 2009 15:00:54 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37037 Nice explanation, John. You threw in some interesting tips on how to make sense of the leap year adjustment idea. Just a quick reminder: <em>the adjustment is only necessary for the months of January and February</em>. Calculations for the other months behave just as in all other years. Nice explanation, John. You threw in some interesting tips on how to make sense of the leap year adjustment idea.

Just a quick reminder: the adjustment is only necessary for the months of January and February. Calculations for the other months behave just as in all other years.

]]> By: Luciano Passuello http://litemind.com/how-to-become-a-human-calendar/#comment-37036 Luciano Passuello Thu, 20 Aug 2009 14:53:55 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37036 It's interesting to see how different people prefer different balances between mental calculations and memorization. Fortunately, the technique is flexible enough to allow tradeoffs at different points. The more numbers you are willing to memorize --- that is, the more effort you're willing to put upfront --- the faster each calculation will be. These are the same tradeoffs we often see in computing, such as 'processing power' vs. 'storage space' --- and, just as those, there's never an ultimate answer. Thanks for sharing! It’s interesting to see how different people prefer different balances between mental calculations and memorization.

Fortunately, the technique is flexible enough to allow tradeoffs at different points. The more numbers you are willing to memorize — that is, the more effort you’re willing to put upfront — the faster each calculation will be.

These are the same tradeoffs we often see in computing, such as ‘processing power’ vs. ’storage space’ — and, just as those, there’s never an ultimate answer.

Thanks for sharing!

]]> By: john http://litemind.com/how-to-become-a-human-calendar/#comment-37035 john Thu, 20 Aug 2009 14:52:48 +0000 http://litemind.com/how-to-become-a-human-calendar/#comment-37035 For a leap year you have to subtract one from your result. Let’s say you have the date February 14 1976. You know the code for February is 4. 14 is zero, and 1976 is code number 4. 4+0+4=8, but you have to subtract one for the leap year. 8 minus 1 is 7, which equals 0. (Saturday) You can always look at the day in the leap year as one less than the original. So if you have to figure out the date for January 15, 2008, just think of January 14th instead. Another way to practice this is to look at the present century. I was born on a Friday. But my birthday for the same date in this century will be on a Thursday. That means that the entire code structure will be one day off for this century. So I do the same thing for dates in this century. I subtract one from the number from the final result. May 26, 1992 was (2+26+3=31) Tuesday. Therefore May 26, 2092 will be on a Monday. For a leap year you have to subtract one from your result.
Let’s say you have the date February 14 1976. You know the code for February is 4. 14 is zero, and 1976 is code number 4.

4+0+4=8, but you have to subtract one for the leap year. 8 minus 1 is 7, which equals 0. (Saturday)

You can always look at the day in the leap year as one less than the original. So if you have to figure out the date for January 15, 2008, just think of January 14th instead.

Another way to practice this is to look at the present century. I was born on a Friday. But my birthday for the same date in this century will be on a Thursday. That means that the entire code structure will be one day off for this century. So I do the same thing for dates in this century. I subtract one from the number from the final result. May 26, 1992 was (2+26+3=31) Tuesday. Therefore May 26, 2092 will be on a Monday.

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