This is a vintage 1980s t shirt depicting a math/science themed image by Sidney Harris.

The tag no longer has the size on it.  So following are the measurements of the shirt, taken with item lying flat. Please use these measurements as a comparison to a shirt that you own that fits you in order to determine fit.

Measuring across the chest (under the arms): about 20"
Across the shoulders (from seam to seam): about 21"
Length from center front collar to bottom hem: about 25"

The model in the last photo is a men's size medium.  He said that the shirt fit him like a modern day large.

This was a beloved shirt in my collection and it was washed and worn about a billion times.  The shirt has no holes or tears.  The hem and seams are intact.  It comes from a nonsmoking home.  Before listing the shirt, it was washed in unscented detergent and dried flat so it is ready to wear. The color of the shirt has a slightly soft faded look, which is consistent with normal wear.  It is a preowned shirt.  It has a tiny, faint mark on the front that I've photographed.  (Please see picture.)  I see a faint mark on the front right arm, which is barely noticeable but I wanted to disclose it.  There is a very tiny divet in the center of the collar, which I highlighted in a detail photo. These do not take away from the wearability of the shirt, but I wanted to let you know about them in advance.

To the best of my ability, I have scrutinized this item for flaws.  Buyer understands that this is a preowned item that is not new and might have other flaws.  Because what might be a flaw to you is a sort of wear and tear that a vintage item would naturally incur.  If you purchase this, you understand that this is a preowned, previously washed, preworn, preloved item.  

It's a cool shirt!  

Payment is to be made upon close of auction.  I do not accept returns for this item. Thank you and happy bidding!