A bag of hammers - When someone is so dumb it's like they were hit by a truck,

When someone is so dumb it's like they were hit by a truck, they're a bag of hammers.

My little brother said the earth is flat. That's a bag of hammers.

My mom said the sky is green. That's a bag of hammers.

My friend said 2+2 is 10. That's a bag of hammers.