Theory Tester Gifts

Searching for the perfect gift for a theory tester? Explore a collection of witty and thoughtful items that capture their passion for testing ideas and solving puzzles. Ideal for those who love to challenge norms and think creatively.

All Products Prints T-Shirts Mugs Pillows

"What good is a crazy theory if you don't put it into practice?"

"What good is a crazy theory if you don't put it into practice?" mockup

"What good is a crazy theory if you don't put it into practice?"

from $19.00

Gregory became an unpopular character after testing his theory that 'all fish could fly'.

Gregory became an unpopular character after testing his theory that 'all fish could fly'. mockup

Gregory became an unpopular character after testing his theory that 'all fish could fly'.

from $19.00

'Essentially Wilkins proves things and Brenner disproves them.'

'Essentially Wilkins proves things and Brenner disproves them.' mockup

'Essentially Wilkins proves things and Brenner disproves them.'

from $19.00

"Well, that blows the hell out of my theory."

"Well, that blows the hell out of my theory." mockup

"Well, that blows the hell out of my theory."

from $19.00

"Finally, after years of work, irrefutable proof that I'm a nerd."

"Finally, after years of work, irrefutable proof that I'm a nerd." mockup

"Finally, after years of work, irrefutable proof that I'm a nerd."

from $19.00

'Thanks to the internet it is now possible to be extremely well-informed and completely wrong at the same time!'

'Thanks to the internet it is now possible to be extremely well-informed and completely wrong at the same time!' mockup

'Thanks to the internet it is now possible to be extremely well-informed and completely wrong at the same time!'

from $19.00

Sigmund Freud.

from $19.00

'If your calculations are correct, this completely revolutionizes everything we thought we knew about why chalk squeaks on a blackboard!'

'If your calculations are correct, this completely revolutionizes everything we thought we knew about why chalk squeaks on a blackboard!' mockup

'If your calculations are correct, this completely revolutionizes everything we thought we knew about why chalk squeaks on a blackboard!'

from $19.00

"I never subscribed to Hobbes' state of nature theory until the night we left the kids without a sitter."

"I never subscribed to Hobbes' state of nature theory until the night we left the kids without a sitter." mockup

"I never subscribed to Hobbes' state of nature theory until the night we left the kids without a sitter."

from $19.00

"Must be another paradigm shift." mockup

"Must be another paradigm shift."

from $19.00

"Bonk!"

from $19.00

"Oh, puhleeese. No one's going to steal your idea."

"Oh, puhleeese. No one's going to steal your idea." mockup

"Oh, puhleeese. No one's going to steal your idea."

from $19.00

"Are you happy with your current ball?" mockup

"Are you happy with your current ball?"

from $19.00

A Freudian slip...

from $19.00

"Mine's bigger than yours."

from $19.00

'I think the professor is trying out the theory of relativity... trying to make time fly!'

'I think the professor is trying out the theory of relativity... trying to make time fly!' mockup

'I think the professor is trying out the theory of relativity... trying to make time fly!'

from $19.00

You can relax now.

from $19.00

Women's sportswear - Sale on paradigm shifts.

Women's sportswear - Sale on paradigm shifts. mockup

Women's sportswear - Sale on paradigm shifts.

from $19.00

"Of course you can't put your finger on it. It's a hypothetical particle."

"Of course you can't put your finger on it. It's a hypothetical particle." mockup

"Of course you can't put your finger on it. It's a hypothetical particle."

from $19.00

'What do you mean 'theoretically'? Everything we do is theoretical.'

'What do you mean 'theoretically'? Everything we do is theoretical.' mockup

'What do you mean 'theoretically'? Everything we do is theoretical.'

from $19.00

"Scientists confirmed today that everything we know about the structure of the universe is wrongedy-wrong-wrong."

"Scientists confirmed today that everything we know about the structure of the universe is wrongedy-wrong-wrong." mockup

"Scientists confirmed today that everything we know about the structure of the universe is wrongedy-wrong-wrong."

from $19.00

Complexity Made Simple.

from $19.00

Physicists disputing whether the clock moves backwards or forwards according to season change.

Physicists disputing whether the clock moves backwards or forwards according to season change. mockup

Physicists disputing whether the clock moves backwards or forwards according to season change.

from $19.00

Darwin first tested his theory in a letter to a magazine ('Lookalike' letter points to similarity between man and ape.)

Darwin first tested his theory in a letter to a magazine ('Lookalike' letter points to similarity between man and ape.) mockup

Darwin first tested his theory in a letter to a magazine ('Lookalike' letter points to similarity between man and ape.)

from $19.00

Theory A Day Calendar.

from $19.00

"Lucky Guess."

from $19.00

Max Weber

from $19.00

"Your IQ came back negative."

from $19.00

A2+B2=C2, 'Are you sure you're not just making this stuff up?'

A2+B2=C2, 'Are you sure you're not just making this stuff up?' mockup

A2+B2=C2, 'Are you sure you're not just making this stuff up?'

from $19.00

Chaos Theory Lecture - Upstairs and ask again.

Chaos Theory Lecture - Upstairs and ask again. mockup

Chaos Theory Lecture - Upstairs and ask again.

from $19.00

"As I mentioned next week in my talk on reversible time..."

"As I mentioned next week in my talk on reversible time..." mockup

"As I mentioned next week in my talk on reversible time..."

from $19.00

'Since you conduct only thought experiments, we were hoping you would, from time to time, come up with some thought results.'

'Since you conduct only thought experiments, we were hoping you would, from time to time, come up with some thought results.' mockup

'Since you conduct only thought experiments, we were hoping you would, from time to time, come up with some thought results.'

from $19.00

'Sorry, Professor Kleinzweck -- your 'Chaos Theory' program just crashed.'

'Sorry, Professor Kleinzweck -- your 'Chaos Theory' program just crashed.' mockup

'Sorry, Professor Kleinzweck -- your 'Chaos Theory' program just crashed.'

from $19.00

'Lately, I've been thinking a lot about evolution. My theory is that it all points to 'survival of the fattest'.'

'Lately, I've been thinking a lot about evolution. My theory is that it all points to 'survival of the fattest'.' mockup

'Lately, I've been thinking a lot about evolution. My theory is that it all points to 'survival of the fattest'.'

from $19.00

'Kleinzweck has a theory that the strong nuclear force is actually tiny rolls of duct tape.'

'Kleinzweck has a theory that the strong nuclear force is actually tiny rolls of duct tape.' mockup

'Kleinzweck has a theory that the strong nuclear force is actually tiny rolls of duct tape.'

from $19.00

Theory Tester Gifts Collection

Theory Tester Mugs

Explore our collection of theory tester mugs for more witty designs that celebrate testing, curiosity, and clever thinking.

Theory Tester Pillows

Add charm and wit to any room with our theory tester pillows. Browse the collection for clever designs that bring comfort and personality.

Theory Tester Prints

Elevate their space with our theory tester prints. Find inspiring and humorous artwork that celebrates testing, thinking, and creativity.

Theory Tester T-Shirts

Looking for more fun apparel? Check out our theory tester T-shirts, perfect for sharing your love of testing ideas with stylish humor.