This paper examines whether Anna Wierzbicka's (1996a, 1996b) hypothesis that the `conditional' and `counterfactual' constructions are semantic universals, can be justified in the case of the Japanese language. Many Japanese constructions are compatible with both condition (IF) and temporal (WHEN) interpretation; despite this, it is shown that there is an unambiguous exponent of the IF-construction in Japanese, which uses the particle moshi. It is also shown that the English `hypothetical conditional' has an equivalent, or near-equivalent, in Japanese. As for the counterfactual, it is argued that while there is an unambiguous counterfactual in Japanese, in the form of a construction with (no)ni, this construction is not a perfect equivalent of the English counterfactual because the Japanese construction always implies that the speaker feels something bad about the real outcome.