As soon as Scottish and English MPs began negotiations for Union in 1706 there was a debate about the two options - an ‘incorporating’ or ‘federal’ Union. The following arguments were made for an incorporating Union.
Disputes
Incorporating meant there would be a shared Parliament. This would avoid disagreements between separate governments in Edinburgh and London.
Power and security
It would mean a reduced threat of foreign invasion and there would be better protection of trade by the Royal Navy.
English desires
Scottish negotiators for Union knew that England would only accept incorporating union.