"A party is not permitted to change his position and adopt a new and different theory on appeal. To permit him to do so would not only be unfair to the trial court, but manifestly unjust to the opposing litigant

It is the general rule that a party to an action may not, for the first time on appeal, change the theory of the cause of action

This argument is not well taken because any putative additional theories were not addressed in Magallanes's opposition to DMC's motion for summary judgment and were not brought to the attention of the trial court

Cal. Jur. 2d 604) and while, as a corollary to the above rule, a party must adhere on appeal to the theory upon which the case was tried below and cannot for the first time on appeal adopt a new and different theory

However plaintiff pleaded and the court found that he was a guest and under the settled rule he is bound on appeal by the theory adopted in the trial court

The essential elements of the doctrine of ostensible authority are: representations by the principal, justifiable reliance thereon by the third party, and change of position or injury resulting from such reliance

"It is therefore declared to be a fundamental rule, never to be lost sight of and not easily to be overestimated, that persons dealing with an assumed agent, whether the assumed agency be a general or special one, are bound at their peril, if they would hold the principal, to ascertain not only the fact of the agency but the nature and extent of the authority, and in case …