The more you take. The less of me you shall have.

I am your aim, yet also your move. I can be right, or fail to prove. I’m both the question and reply What am I? Don’t overthink. Just take a small.....

I study your choices, shaping your view, feeding you echoes of what you once knew. The more that you give, the more I return, until my desires feel like your own.

It's not real but does exist, it helps to determine where a plane will drift, you'll see it in math but never on a ruler, and it was first annotated by a man named Euler

I come with cells for you to complete; using numbers and logic I can be beat. What am I?