I was rewatching Secret of My Excess (season two, episode 10) this morning, when I realized Rarity gives us the perfect scale for measuring the height of ponies!
This is absolute proof of the ponies actual size! Rarity is an expert on gems!
You wouldn't call Rarity a liar would you? WOULD YOU!?
Who would have known that the pony toys they sell at Walmart are life size representations!
Edit: Confirmed as canon by Larson! twitter.com/M_A_Larson/status/…