This is an interesting question. In this economic situation, I would say that accounting must be science. Accounting is about numbers and being transparent, so that all who need to know anything about a company has all the necessary information. This point is very important to emphasize, because we all learned the hard way that often times accounting practices can be too creative. This is a nice way of saying that there has been too many lies and false information given. Think of the Enron scandal and eventual collapse of the company. We are also seeing "creative" account practies with Greece, which is causing problems for the world.
Even today, Bloomberg has come out with an article about how much money each bank received in 2008 in bailouts. In light of all these scandals, accountants must be exact and transparent.
With all of this said, there is room for creativity. But if there is anything creative, then it must be divulged.
If you ask me, I would say science. It might not use the scientific method for each and every minute calculation, but it does deal with data, data analysis, creating conclusions, and working problems. That sounds quite scientific to me. However, if you were to ask my brother (who happens to be an accountant), he would say that there is quite a bit of art to it as well. He would clarify the statement though by saying that doing the every day, mundane spreadsheet stuff is not art. What is art in his line of accounting is how he must display the pertinent information to his clients. My brother knows all about the ins and outs of accounting and tax law, but the clients do not. My brother works creatively in presentations to take a bunch of complex data sets and present them in a way that is both informative and eye catching. That's art.
By definition, the act of accounting is the process of analyzing data, reporting it, and documenting financial transactions in a systematic and uniform way. This being said, the fact that accounting has exact methodologies by which the reporting and documenting is done precludes that it follows a pseudo scientific method. By scientific it does not mean that it follows the same procedure used in medical sciences, but that it follows a solid, concrete and effective series of steps that can be repeated by different people and still have the same results.
When it comes to quantities, amounts, and working with numbers in general it is imperative to have a system that proves to be exact and can be repeated with the same results. In that sense, accounting is a science.
However, as with every science, all of those who are successful and have a special gifted technique may define their talent as an art. That is, the act of accounting itself is not considered an art, but the process of accounting in a way that is unique an effective at the same time is certainly an artistic product.
I think accounting is both science and an art. It is science because it requires/undergoes step by step process. and an art because it has a proper format or style like the way entries/accounts are written..