Perustuessaan

Perustuessaan is a Finnish non-finite verb form of perustua, meaning to be based on or to be founded on. It functions as an adverbial participle (converb) and is used to indicate the basis or foundation for a statement, conclusion, or action. In English, it is often translated as based on or on the basis of.

Formation and use: The form arises from the verb perustua with the -essaan/-essään ending, creating a subordinate, non-finite clause that expresses basis or premise. The clause introduced by perustuessaan typically provides the evidential or logical ground for the main clause. The subject of the subordinate clause is usually the same as the subject of the main clause, though context can allow shared or understood references. This construction is more common in formal or written Finnish than in everyday speech.

Meaning and function: Perustuessaan conveys a sense of foundation or justification for what is stated in the main clause. It does not denote a separate finite action by a different subject; rather, it marks the basis on which something stands or is concluded. In translation, it frequently corresponds to phrases like “based on,” “on the basis of,” or “as it is based on.”

Related forms: A closely related present participle form is perustuessaan in the sense of basis in a clause. Other related expressions include perustuen (often meaning “based on” in a more general sense) and phrases using perustua with a noun phrase to express basis.

Examples:

- Päätökset tehtiin perustuessaan useisiin todisteisiin. (The decisions were made based on several pieces of evidence.)

- Käsittelyperiaate on muuttunut perustuessaan uuteen oikeuskäytäntöön. (The interpretive principle has changed based on new jurisprudence.)