Well, it really depends a bit on what you plan on putting in, but to get any kind of air flow, you need to move air from one point to another. Hot air goes up, so if you plan on putting a fan on the outside and have it blow air in, without any exhaust ... it'll do nothing. Either on the bottom of the case (and raise it off the floor or carpet!) or on the side, you should prepare some air intake. The fan can be inside, blowing hot air out, if it is on the top facing up, or o, the back, like next to the back plate, blowing air out. If you do it that what then it should not be a big issue theoretically.
If you use watercooling and you have no discrete (separate) graphics card, you still need air intake, but you could move the radiator outside of the case. In theory. Depends if the hoses are long enough.
Depending on your CPU, you can also at times, even completely not need cooling, but you will need air flow! There are T spec'ed processors with a TDP of 35W or so, so that can do with passive heat sink, and a case fan extracting hot air near by this heat sink.
Interesting. Wood case. Huh. My wife has a cooky jar I been looking at ... I may give that a go...
