
I hope you get every puzzle in this book wrong. I’m being honest. The more you answer incorrectly, the more fun you will have . . . Guardian puzzle master Alex Bellos knows better than anyone that the puzzles we find irresistible are the ones that deceive us. Those that seem blindingly, obviously simple – and yet we can’t help but get wrong. These 70 confounding puzzles – which Alex has scoured from across psychology, mathematics, statistics, physics, geography, the science of perception and more – are guaranteed to catch you off guard. But why are you getting them wrong? And how can you get them right? In Think Twice, Alex delights in tripping us up and then returning us to our feet, explaining how these puzzles work, the biases holding us back – and how to train your brain to avoid being hoodwinked again. Think once and you will stumble. Think twice and you are in with a chance. Now that you’ve been warned, can you prove Alex wrong?
Hand wash only
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Standard Delivery
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Express Delivery
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Next Day Delivery
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£2.49
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£3.99
Evri ParcelShop | Next Day Delivery
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Premium DPD Next Day Delivery
£7.99
Bulky Item Delivery
£4.99
Northern Ireland Super Saver Delivery
£2.99
Northern Ireland Standard Delivery
£4.99
Northern Ireland Express Delivery
£5.99
Unlimited free delivery for a year with Unlimited Delivery for £14.99
Please note, some delivery methods are not available for products delivered by our brand partners & they may have longer delivery times
Something not quite right? You have 21 days from the day you receive it, to send something back.
Please note, we cannot offer refunds on fashion face masks, cosmetics, pierced jewellery, adult toys, and swimwear or lingerie if the hygiene seal is not in place or has been broken.
Items of footwear and/or clothing must be unworn and unwashed with the original labels attached. Also, footwear must be tried on indoors. Items of homeware including bedlinen, mattresses, and toppers, and pillows must be unused and in their original unopened packaging. This does not affect your statutory rights.
Click here to view our full Returns Policy.

I hope you get every puzzle in this book wrong. I’m being honest. The more you answer incorrectly, the more fun you will have . . . Guardian puzzle master Alex Bellos knows better than anyone that the puzzles we find irresistible are the ones that deceive us. Those that seem blindingly, obviously simple – and yet we can’t help but get wrong. These 70 confounding puzzles – which Alex has scoured from across psychology, mathematics, statistics, physics, geography, the science of perception and more – are guaranteed to catch you off guard. But why are you getting them wrong? And how can you get them right? In Think Twice, Alex delights in tripping us up and then returning us to our feet, explaining how these puzzles work, the biases holding us back – and how to train your brain to avoid being hoodwinked again. Think once and you will stumble. Think twice and you are in with a chance. Now that you’ve been warned, can you prove Alex wrong?
Hand wash only
49p delivery on all orders over £30 (exc. Bulky Item Delivery)
Super Saver Delivery
£2.99
Standard Delivery
£3.99
Express Delivery
£5.99
Next Day Delivery
£6.99
24/7 InPost Locker | Shop Collect
£2.49
Evri ParcelShop
£3.99
Evri ParcelShop | Next Day Delivery
£5.99
Premium DPD Next Day Delivery
£7.99
Bulky Item Delivery
£4.99
Northern Ireland Super Saver Delivery
£2.99
Northern Ireland Standard Delivery
£4.99
Northern Ireland Express Delivery
£5.99
Unlimited free delivery for a year with Unlimited Delivery for £14.99
Please note, some delivery methods are not available for products delivered by our brand partners & they may have longer delivery times
Something not quite right? You have 21 days from the day you receive it, to send something back.
Please note, we cannot offer refunds on fashion face masks, cosmetics, pierced jewellery, adult toys, and swimwear or lingerie if the hygiene seal is not in place or has been broken.
Items of footwear and/or clothing must be unworn and unwashed with the original labels attached. Also, footwear must be tried on indoors. Items of homeware including bedlinen, mattresses, and toppers, and pillows must be unused and in their original unopened packaging. This does not affect your statutory rights.
Click here to view our full Returns Policy.
Extend your warranty and protect your purchase against accidental damage and defects.
Protects your new Think Twice against breakdowns and faults once the manufacturer's warranty period is over.
Covers issues not included in your manufacturer's warranty, such as accidental damage or theft.
Get a replacement or a cash refund up to the full amount you originally paid for it.
FAQs
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